You can set how many days Box Trapper will keep the mail logs on the server:

Simply click on "Box trapper Spam Trap" under Email Managment,Click "Manage" next to the email address you want to adjust.Click "Configure Settings"Type in a new number into the third text field "How many days should logs and messages in queue be kept" and click "Save".This must be done for each user as each user's settings are independent of the other users on the account.